--- title: "Grignard reagent + ester → 3° alcohol Template | MolDraw" url: https://www.moldraw.com/templates/grignard-ester-double-addition/ description: "Grignard reagent + ester → 3° alcohol template: PhMgBr adds to methyl benzoate; the tetrahedral intermediate expels methoxide to give benzophenone, which is…" lang: en publisher: Scidart Academy generated: 2026-11-13 --- [MolDraw](https://www.moldraw.com/) › [Templates](https://www.moldraw.com/templates/) › [Name reactions](https://www.moldraw.com/templates/name-reactions/) › Grignard reagent + ester → 3° alcohol [Name reactions](https://www.moldraw.com/templates/name-reactions/)Premium # Grignard reagent + ester → 3° alcohol template ![Grignard reagent + ester → 3° alcohol template: PhMgBr adds to methyl benzoate; the tetrahedral intermediate expels methoxide to give benzophenone, which is more reactive than the ester and takes a second PhMgBr; acid work-up gives triphenylmethanol.](https://www.moldraw.com/templates/grignard-ester-double-addition.webp) [Edit in MolDraw](https://www.moldraw.com/)Download with Pro Premium template. Preview and edit it free in MolDraw; downloading and exporting it is part of [MolDraw Pro](https://www.moldraw.com/pricing). PhMgBr adds to methyl benzoate; the tetrahedral intermediate expels methoxide to give benzophenone, which is more reactive than the ester and takes a second PhMgBr; acid work-up gives triphenylmethanol. ## Mechanism step by step Addition, loss of methoxide to a ketone, then a second addition: two equivalents of R–MgBr 1. **First addition** – The C–Mg bond attacks the ester C=O 2. **Loss of methoxide** – C=O re-forms and MeO⁻ leaves: benzophenone 3. **Second addition** – The ketone reacts faster than the ester: a second PhMgBr adds 4. **Acid work-up** – The alkoxide is protonated ## Key points - The ketone formed in step 2 is more electrophilic than the ester, so it captures R–MgBr at once: the reaction cannot be stopped at the ketone, and 2 equivalents are needed. - Two of the three groups on the carbinol carbon come from the Grignard reagent: RCO₂R′ + 2 R″MgBr → RR″₂C–OH. Formate esters give secondary alcohols. - Strictly dry conditions: water or any O–H/N–H protonates PhMgBr to benzene. Biphenyl (from coupling while the reagent forms) is the usual by-product. - To stop at the ketone, use a Weinreb amide or a nitrile: their tetrahedral adducts do not collapse until work-up. Drawn with 193 atoms, 13 arrows, 8 shapes – every one editable in MolDraw. ## Sources - [Clayden, Greeves & Warren, Organic Chemistry, 2nd ed., OUP 2012, ch. 10](https://openlibrary.org/isbn/9780199270293) Textbook - [Kürti & Czakó, Strategic Applications of Named Reactions in Organic Synthesis, Elsevier 2005](https://openlibrary.org/isbn/9780124297852) Textbook ## How to use this template 1. Press **Edit in MolDraw**. The template opens on the canvas of the free MolDraw editor. 2. Change anything: move structures, edit atoms and labels, recolour highlights or delete what you do not need. 3. Add your own structures, arrows and text next to it, or combine several templates on one page. 4. Export the drawing as PNG, SVG or PDF for slides, worksheets, theses and papers. ## Frequently asked questions ### Is the Grignard reagent + ester → 3° alcohol template free? You can preview the Grignard reagent + ester → 3° alcohol template here and open and edit it in MolDraw for free. Downloading or exporting it is part of MolDraw Pro, together with the other premium templates. ### Can I edit the Grignard reagent + ester → 3° alcohol template? Yes. It opens as an ordinary MolDraw drawing, so every structure, arrow, label and colour can be changed, and you can add your own content around it. ### Is the chemistry checked? Every structure is checked with RDKit and every curly arrow passes MolDraw’s electron-flow audit. The sources used are listed on this page. ### Which name reactions are included? Over seventy, covering the reactions most often asked in school-leaving exams (A-level, IB, CBSE, JEE and NEET) and first-year university courses, including condensations, rearrangements, oxidations, reductions and aromatic substitutions. ## More name reactions templates [**Fischer esterification**Free · Name reactions](https://www.moldraw.com/templates/fischer-esterification/)[**Grignard addition to a ketone**Free · Name reactions](https://www.moldraw.com/templates/grignard-addition/)[**Michael addition**Free · Name reactions](https://www.moldraw.com/templates/michael-addition/)[**Diels–Alder reaction**Premium · Name reactions](https://www.moldraw.com/templates/diels-alder/)[**Friedel–Crafts acylation**Premium · Name reactions](https://www.moldraw.com/templates/friedel-crafts-acylation/)[**Claisen condensation**Premium · Name reactions](https://www.moldraw.com/templates/claisen-condensation/)[**Friedel–Crafts alkylation**Premium · Name reactions](https://www.moldraw.com/templates/friedel-crafts-alkylation/)[**Cannizzaro reaction**Premium · Name reactions](https://www.moldraw.com/templates/cannizzaro-reaction/) ## Related pages [**Curved Arrow Mechanism Worksheet**Free printable worksheet](https://www.moldraw.com/educational-materials/curved-arrow-mechanism-worksheet/)[**Predict the Product Worksheet: Organic Reactions**Free printable worksheet](https://www.moldraw.com/educational-materials/predict-the-product-worksheet/)[**All Name reactions templates**93 templates](https://www.moldraw.com/templates/name-reactions/)[**All chemistry templates**525 templates in 31 categories](https://www.moldraw.com/templates/) MolDraw Pro Download all 525 templates - Export the 437 premium templates as PNG, SVG or PDF - AI chemistry assistant - Structure scanning from images - Cloud save and teaching slides [See Pro plans](https://www.moldraw.com/pricing) Free templates stay free. 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